Ethnic Differences in Dietary Intake and the Association between Dietary Intake and Gastric Cancer Risk in Chinese Subjects Resident in Malaysia

Abstract

Introduction: Non-cardia gastric cancer (GC) is a multi-factorial disease. Currently it is believed that Helicobacter pylori infection, host genetic and dietary factors play a role. Aim: This study determined the influence of dietary factors in the etiology of GC in Chinese subjects resident in Malaysia and differences in dietary intake in 3 ethnic groups resident in Malaysia and Singapore. Subjects and Methods: 317 subjects with functional dyspepsia (FD) including 123 Chinese, 110 Indians and 83 Malays and 54 Chinese with GC resident in Malaysia and 127 Chinese FD subjects resident in Singapore were included in the study. Genotyping of IL-1B-511 and IL-1B-1473 was conducted by PCR-RFLP. H. pylori infection status was evaluated by ELISA. The dietary questionnaire explained by a nurse, was completed by each patient. Results: Significant differences were observed in the intake of alcohol, salted fish, shrimp paste, salted vegetables and fresh fruit and vegetables for the three main ethnic groups in Malaysia and between Malaysian Chinese FD and Singaporean FD patients. A significant association was observed between alcohol intake, fresh fruit and vegetables intake and shrimp paste intake and the risk of GC in Chinese resident in Malaysia. When a combination of specific host genetic factors, dietary factors and H. pylori infection were considered there was a significantly increased risk of GC; these factors being the C/C genotype of IL-1B-511, the G/G genotype of IL-1B-1473, low fresh fruit and vegetable intake and H. pylori (+). Discussion: In this population, H. pylori infection, host genetic and dietary factors are significantly associated with GC development. Beside the differences in H. pylori infection and host genetic factors, the differences between different ethnic groups in dietary factors may also contribute to different frequencies in GC.